The present invention relates to flow measuring devices and, more particularly, to a hot wire anemometer flow meter adapted to measure fluid flow within a conduit such as that utilized in downhole gas, oil well, or geothermal applications.
As is well known in the oil and gas industry, it is usually advantageous and often necessary to measure the flow in an oil or gas line to determine or forecast well production. Heretofore, the most common practice in the industry was to insert a turbine flow meter down hole which upon rotational movement of the turbine rotor, generated an electrical signal representing the flow through the well. Although such prior art turbine flow meters have proven generally effective in their intended application, they possess inherent deficiencies which have detracted from their overall effectiveness in the trade.
Foremost of these deficiencies has been the inability of the prior art turbine flow meter devices to provide accurate flow measurements in turbulent flow or combination laminar/turbulent flow conditions. Further, the prior art turbine flow meters have typically yielded inaccurate measurement results in two phase (i.e. water and soil) or three phase (i.e. water or oil and gas) flow conditions. In addition, the operation of the turbine flow meters is dependent upon a generally vertical or axial orientation within the line which has rendered their use inappropriate for many of the more modern well applications, which utilize angularly extending well drilling techniques. Additionally, the prior art turbine flow meter devices have typically been incapable of being disposed down hole for extended periods of time to record long term changes in the flow within the well.
Hence, there exists a substantial need in the art for an improved down hole measuring device which provides both flow speed and direction measurements, is accurate in both turbulent and/or laminar flow conditions, can be utilized in singular, double, or triple phase flow applications, and is not dependent upon orientation within the flow line.